Seventh Gear!
 

Finally got around to putting my money where my mouth is, and installed a Gear Vendors overdrive on the Red Baron. Just did a test drive and still have a couple of small installation issues to work out, but this is gonna be sweet.

1125 RPM @ 60 MPH EGT: 475 degrees pre-turbo.

I also did some other work - chamfered my swollen brake pads, set camber and toe-in dead on zero, and I'm trimming back the air dam, so I'll need a month to re-baseline the truck's MPG. Then I'll get a valid 1500 mile test on the MPG.

Is the Baron ever heavily loaded/pulling?

Its loaded or pulling a trailer about as much as most pickups.

I'll do some loaded tests with this setup.

I saw that Ford had some folks test their new Super Duties with a 1,000 load. 25 bags of anthracite should nicely mimic that one.

what is final drive?

60 @ 1150..nice.

I asked because once upon a time I considered the GV OD too. I came to the conclusion that one would have to put on one hella lot of miles for it to pay off- as you well know they aren't cheap. And I thought unless the truck is really, really heavily loaded (of course this is from a flatlander's perspective) there is no need for more gears; just a desire for a taller cruise gear. AND I thought since the goal is efficiency, adding another set of gear meshes, shafts, bearings, oil sump, weight, and whatnot to the drivetrain actually decreases the drivetrain efficiency as far as friction losses go, but ODs show an fe gain due to the tall ratios... therefore, for the lightly loaded flatlander truck the best thing to do would be gear up with tall diff gears and/or tall tires.

Actually the notion that more gears i.e. 5, 6, 7, and ? speed transmissions increase efficiency is kind of lost on me... because even with a 5 speed stick, with my mostly lightly loaded driving conditions I end up skip-shifting almost all the time anyway... well if I'm ignoring 2 gears and treating the car like a 3 speed, I think an actual 3 speed trans would be more efficient because there would be two fewer gear meshes, and gear meshes take power even when they are transmitting none.

P.S. Back in the '80s Ford offered a 4 speed m/t in their High Efficiency version of the Tempo/Topaz, NOT the 5 speed...

In some cases, it's a bad idea to set toe-in to 0 on an idle truck because of "scrub angles" of the tires.

Not saying this is the case with your truck, but the proper way to dial in the toe for the least drag at a given speed would be to measure the average suspension height at that speed, and set it so that suspension travel and scrub angle sets the tire to 0 toe at the speed you want.

IE if you hold 75, figure out where your suspension is on average at 75 on a flat, smooth, level road (yeah, right), and determine 0 toe for that suspension load, and then (I have no idea how to do this part) calculate the angular load against the tires for that speed and set the toe inward enough to combat it at that speed.

However: This may not apply to your truck. I don't know if toe angles are changed with I-beam front suspension and a non-R/P steering setup. I don't think they are. Scrub angle still applies, though, for the record.

Actually zero is within the specified range for both toe-in and camber, so that is not all that radical a setting.

The idea of more speeds is to eventually get the engine RPM at a given road speed to a minimum without a big jolt in engine speeds.

Low engine speed at a given riad speed has long been effective for improving MPG because it minimizes engine frictional HP. This loss is protional to engine speed below 2000 RPM in the T444 and slightly hyperbolic above.

This mod is pricey, but in my view this truck is now a form of hot-rod and not just some weak "duct tape and coroplast" dabbling.

If I don't mess up my air dam, I expect 30 MPG. There is no EPA mileage for this truck but most guys report 14-16 MPG, so I'll have the average effectively doubled.

:thumbup:

I'm trying to get to that stage myself.



Btw, the Ford Fusion hybrid has no reverse gear, just electric reverse.

I can't remember the last time I used 4th gear on my car. When I'm PHEV'ing, I skip 2nd as well. It feels like I have enough torque to do a clutchless 3rd gear launch, if I had the right software, which would give me a 3-5 shift.

Yup, I could picture a really efficient car with a two speed tranny and no reverse gear.

But you want to get in top gear a.s.a.p. Less shifting = top gear sooner.

Heavy loads + uphills = jolts.

Empty + flat = not so much.

This mod is pricey, but in my view this truck is now a form of hot-rod and not just some weak "duct tape and coroplast" dabbling.


Yup . . braggin' rights ain't cheap. But that GV would sell overnight on Ebay, so it ain't much of a risk.

I'm all the time reaching for mystery seventh on the occasions I get past 60 mph entering the highway.

It would be a heckuva lot of fun on one of these light duty trucks to have a 10-speed that didn't weigh as much as the engine . . perfect gear choice at every posted speed.

So, even though this thing has a motor stolen from the special ed short bus ;) . . we're looking forward to how it works out.

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I wondered when a competitive Dodge Cummins guy would show up, even though they are limited in MPG by that lawn-sprinkler injection they have.

On other forums, Dodge and Chevy guys tell me how much better MPG Cummins and Duramaxes get. My answer is always the same: Road trip!

Cricket city.

That Cummins should be able to hack 870 RPM @ 40 MPH, one would think.

I wish I could do something similar for my festiva. It has a ridiculous power to weight ratio now and I can cruise along in 5th at 25mph and 1000 rpm and still pull up to 55mph in no time. 55 is about 2300rpm. I even swapped out the .8 5th for a .71 5th and theres still plenty of rpm and cruise. I bet it could easily chug along at 1500rpm without a problem. Theres only one taller 5th gear for the g25mr and its a .68, from the diesel mazdas that were never sold here. and .68 might drop me what, 100 rpms? Not much improvement. I dont think theres any 6 speeds that would bolt up to the B-series engine and even then the g25mr is a tight squeeze in a festiva, I cant imagine anything bigger.

I find myself trying to shift into a nonexistent 6th gear on the road. I am not sure what my revs are in 5th but they sound too high for my liking. But they might sound that way because I cut the exhaust off under the cab.....

Man, I'd never even thought about trying that. I'm pretty uncomfortable at anything under 1,100-rpm. The gearing is such, however, that in Direct (5th of 6 gears) 45-47 mph sure would be interesting.

So what's that thing show on a ticket from a certified scale? I was reading some foolishness on a Fordbord one day where the participants were trying to justify their heavier-than-the-competition trucks would therefore be able to "better handle trailer sway". After I stopped laughing I went back to searching to see what those trucks benefitted by in re mpg (after reading your posts on here).

I find these trucks pretty insensitive to the first 1,000-lbs payload (given a highway run) but I didn't search long enough to see what your brand was reporting.

(As a one-time train driver you'd appreciate seeing Laredo. Might be a little slower these days, but the traffic volume -- out in the middle of nowhere -- is impressive. Not quite the Bailey Yard in Platte, but impressive in its own way).

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Man, I'd never even thought about trying that. I'm pretty uncomfortable at anything under 1,100-rpm. The gearing is such, however, that in Direct (5th of 6 gears) 45-47 mph sure would be interesting.

So what's that thing show on a ticket from a certified scale? I was reading some foolishness on a Fordbord one day where the participants were trying to justify their heavier-than-the-competition trucks would therefore be able to "better handle trailer sway". After I stopped laughing I went back to searching to see what those trucks benefitted by in re mpg (after reading your posts on here).

I find these trucks pretty insensitive to the first 1,000-lbs payload (given a highway run) but I didn't search long enough to see what your brand was reporting.

(As a one-time train driver you'd appreciate seeing Laredo. Might be a little slower these days, but the traffic volume -- out in the middle of nowhere -- is impressive. Not quite the Bailey Yard in Platte, but in its own way).

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Maybe we can work something out. I've been wanting to come to TX to talk aerodynamics with the guru.

I'm like you. The first 1,000 lb doesn't seem to matter very much. To me the classic pickup load is a load of 4x8s up the the bed rail.

I think a truck should be able to be loaded full of wood or dirt and still be ok. I know that is a tall order but why put a bed on a truck if you can't fill it? My cousin has a ranger and you can get about 300 lbs in it and it squats. SAD.

Springs must be shot. That does happen sometimes.

It was like that when it was new. Maybe add a leaf.

Rangers don't squat with only 300 lbs in the back. I know that for a fact; I have one. Moon Unit barely squats with 300 lbs on the trailer hitch tongue.

1310 RPM @ 70 MPH indicated.

Its weird what you can hear when the engine isn't roaring so loud.

Zero toe-in and camber makes the truck a bit twitchy. It feels like a crosswind in dead calm.

I wish I could afford that GV rear bob.
I'm running on 4.10:1. Talk about reaching for a 6th gear on the highway.
I have a taller set of tires I put on to get the rpms down. They help but I got lazy once and left them on while towing. Lets just say the hills weren't much fun and I was glad I had the granny gear.

On the twitchy part, try a stiffer steering dampner. (The shock bolted to your steering arm) The ones for big mud tires are stiffer. It will make for nicer towing as well, less arm fatigue.

If caster is adjustable more of it should help.

That's why nominal toe is usually slightly toe-in for RWD vehicles. Sure, zero is "in-tolerance" but a slight static toe-in allows for dynamic loads and bushing compliance without losing the on-center feel.

A stiffer steering damper (if you even have one) won't reduce twitch due to inadequate toe-in as that feeling is a result of variations in tire grip from side to side pulling the truck in the direction of the tire, not due to motions within the steering linkage.

Higher caster angles (and stiffer dampers too) increase steering effort. More caster increases the return-to-center moment due to increased trail, but if your "center" is toed-out under driving load your twitchy handling may continue even if slightly diminished because your tires will still point away from center. As your weight shifts to the left the truck will pull left and vice-versa, plus it should follow road crowning pretty strongly.

Haha I think this is pointing at my car and other similar ones around here lol.
congrats on doubling the normal MPG of your truck - I consistently use you as an example to my brother and other HD truck driving friends.

Having driven it some, I think I'm gonna live with it as-is. It isn't THAT twitchy, just more than it was. The long wheelbase stabilizes it a lot.

The upside is my coasting distances have gone berserk. On a 0.6 mile coast from 70 to a stop light, I used to just coast up to the stop light. Now I'm going 40 MPH at the light and have to jam on the binders. Hence, next time I start my coast farther out. This is with my tires aired down to 80 psi. Before I was at 100 psi.

With two drive shafts there is a small amount of increased drive line "snatch" but it is managable and I'll smooth it out in a week or so.

At speeds under 65 MPH, my engine is now normally aspirated - zero boost.

EGT stays in the happy zone: <600 degrees F (pre).

The truck's whole acoustic signature is different with the roar of the engine attenuated. I can hear a front wheel bearing just beginning to rumble.

my coasting distances have gone berserk. On a 0.6 mile coast from 70 to a stop light, I used to just coast up to the stop light. Now I'm going 40 MPH at the light and have to jam on the binders. Hence, next time I start my coast farther out


Can it coast all the way across Illinois?


I, too was wondering about the steering affect (alignment witchery).


At speeds under 65 MPH, my engine is now normally aspirated - zero boost.

EGT stays in the happy zone: <600 degrees F (pre).


Wild . . . .


We gonna get some weight stats (empty and loaded) for a range? Curious minds want to know . . it currently weighs 7,900-lbs, and generally ranges to over 9,000-lbs?


I've been wanting to come to TX to talk aerodynamics with the guru.


North Texas would be about half the distance from Indiana to South Texas. Better charge the A/C back up if it isn't between November and April.

Keep it coming. I hope you'll think on doing some video. A-B per cab noise would be cool. As would some shots from other cars showing how far that thing can roll. I'll have to break some rules about cheering for Fords.

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I don't think I can coast across whole states. It ain't a 12,000 ton train rolling on steel wheels/rails, but I'm still adjusting my coasts.

Truck curbs at 7,600 lb and GVWR is 9,900 lb. I'm running empty right now.

Astonishingly to me, despite the huge overdrive ratio and tall final drive, this thing still can accelerate at 70 MPH in seventh gear.

I always thought my OEM Firebombs were pretty quiet.

Now without the engine roar @ 70 MPH, I can hear them howl.

Sure wish somebody would update the LRR tire list.

Man do I envy this whole thread.

It's no powerlifter and frankly East TN is really pretty hilly, but my old Yota has the twist to turn a sixth gear, hills included. The speedo is so far off, it's exactly right for if I was running a 3.35 rear, but I'm pretty sure the 3.73 was always the right ratio. But an extra gear up top, boy that'd be good.

Kudos, Dave - I'm really looking forward to seeing how this turns out.

desperately need an extra cog in my little diesel polo - only running 26mph/1000rpm in top.

so envious

I'd love taller gearing for my Jeep. I turn about 1825 rpm at 60mph with stock tires and stock 3.73 gears. Going from the small-ish stock size of 225/70/16 to a 245/70/16 (optional size) will get me down to 1750 and give me a little more ground clearance to the diffs for offroad.

If it wasn't for the insane cost and amount of fab-work required, I'd love to swap in a T56 with either a 2.97 1st gear and the super-tall 0.5 6th, or the more common 2.66 1st / 0.5 6th, and regear the axles to 4.56 or 4.88, that would give me a stick, plenty of low end power, and still lower highway rpm (4.56 would be 1560 at 60mph, 4.88 would be 1670 at 60mph). If I kept the stock 3.73s and did that, my off the line power would be lacking a bit, and I'd be dropping out of 6th on most hills turning only 1270 at 60mph.

Couple of thoughts about comptiger's Jeep Grand Cherokee.

1. I don't think T-56 trannies can be fitted to a transfer case.

2. You don't want to slow the engine down by using larger diameter wheels/tires. That decreases MPG because it increases rotational moment of inertia of the wheels/tires. RMI goes up with the square of radius. They become bigger flywheels and you have to pour energy into them to accelerate or decelerate. Pickup truck guys find this out often to their sorrow. I've tried both ways - bigger and smaller and found this is something the factory boys get right.

3. A GV costs more than a T-56 but it indestructible. I looked into a T-56 but the vast torque of my diesel and the road load a pickup can develop (heavy load going uphill or pulling a traler for hours on end) would trash a T-56. Yes, I know T-56s are used in Corvettes and Vipers, but these arelight cars with powerful engines. They don't really put that much toque through the transmission. The GV was developed for a British Bedford deuce-and-a-half military truck.

4. Because it is so aerodynamically hopeless, your Jeep would be a great project just to show what you can do with gears.

5. Randy's Ring & Pinion sell Yukon R&P set for the Dana 44 down to 3.08:1.

What I'd recommend: Stay with stock diameter tires and go skinnier. "Pizza cutters" are generally fine snow tires. Then swap in 3.08s in the axles. Either that or stay with the 3.73s and put in a GV. That would yield you 2.98:1 gearing. That would cost you about $700 more than regearing two axles but you can cut it out when you like.

I originally thought the same about mounting the T56 to a t-case. However, it's apparently been done before with adapter plates and/or a different tailcone.

A stock T56 is rated for 400 - 450 lb. ft. of torque, my engine puts out 345. So that even leaves a little room for growth, especially if I used a beefier aftermarket T56 rated for more torque. For around town mileage, if I were going to do anything, I'd like to ditch the auto tranny. The t56 would give me that, and a good ratio spread. I could also do an NV3550 or something + a GV. Also, I know that I can get gears for both my D44a rear and D30 front in 3.08, 3.55, 3.73, 3.92, 4.10, 4.56, 4.88, and maybe 1 or 2 other steps.

As far as the tire size, the purpose of the slightly larger tires (about 3.8% taller) wasn't to get the RPM down. That's just a bonus effect. Plus, they're only a little heavier. (31lb for current rear tires, unsure of fronts, 33 or 35 lb for planned new tires, depending on which I get, either Toyo Open Country A/T or Firestone Destination A/T). The weight hurts mostly around town anyway, and the mileage is so hopelessly crappy around town, I don't think it would make more than 0.1 mpg difference.

The only aero mods I have planned for now are some not-too-heavy skid plates to clean up the underbody air flow a bit, and offer some protection down there. Otherwise, I plan to do it all with gearing and engine mods (better injectors are said to help, and about $140).

Bone stock, I was able to average 19.2 mpg last weekend running on the highway (no trucks) at 65mph average, including 2 miles of stop and go traffic, with the A/C on the whole time, and with some rain.

WOW! My truck turns 1450rpm at 60mph and 1700rpm at 70mph. This is with 325/55R22 tires and 3.73 gearing with my 4 speed auto (48RE) tranny. Mine runs around 1-2psi at 60mph on flat/level road. I've been getting 23mpg+ tanks lately with no aero or really much eco driving at all. I can't wait to see the improvements you will have with the GV in that ford. BTW mine will do 35mph at 850rpm locked in o/d.....up grades it will smoke a little though!

I've got a 46RE (same ratios as 48RE) and 3.73, so the only gearing difference between yours and mine is the tire size. I know mine will climb a hill and have enough power to just start to gain speed before I hit the downshift point in OD locked at 1100 (36mph, any slower and it unlocks the TC). It's good enough to have surprised a few people that it did that and isn't a diesel.

I could probably lug it down to 800 locked up on the flats at 30 - 40 mph. I wouldn't want to go below 1000 - 1200 on the hills though.

Sorry about taking so long for results.

Had some alignment issues. Truck trying to shake itself to bits. This divorced gearbox setup has a lot of scope for misalignment.

Should get tests going shortly.

Boooo I wanna see some numbahs!

Better a lackanumbahs than listening to me bellyache about broken-down machinery.

It seems to be fixed now. I can start testing after the Fourth.

Came across a guy today with Cummins 4bt conversion into his 2001 1500: 27 city & 33 highway. Teething problems but nice work to view:

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